The present invention relates to devices and methods for creating real images and, more particularly, to an apparatus and method for creating a real image illusion having enhanced visual and other special effects.
Real images have been used for many years to create optical illusions and other special effects which amuse and entertain the public. Real images are created when light is reflected from a real object and focused toward a region corresponding to the real image. Various optical systems have been used in the past to generate real images. The most common optical systems use either transmissive optics or reflective optics, such as spherical or parabolic mirrors, in combination with a real object. Other common means for creating real images, in addition to transmissive and reflective optics, include holographic optical elements and the like.
One common reflective optical system for creating real images is described in U.S. Pat. No. 4,802,750. It comprises two paraboloids of revolution in the form of parabolic reflectors which face each other at an offset angle. A real object placed in the focus region of the first or primary reflector produces parallel light rays. The other, secondary reflector receives these parallel light rays and refocuses them to create a real image in the focus region of the secondary reflector. Parabolic reflective optical systems such as these are generally regarded as producing the clearest and sharpest real image available, since spherical reflectors only approximate the desired visual effect and produce a relatively blurred image that distorts heavily when viewed from an off-axis location.
While real images have the potential to be a very powerful technique for creating optical illusions and other special effects, the present systems for creating real images have several limitations which inhibit more versatile and effective use of the technique. For example, observers who are viewing the real image are able to see the source optics that create the image. The ability of observers to see the source optics eliminates the element of magic and intrigue associated with the image. Furthermore, the unsightly source optics detract from the special visual effect of the optical illusion. At present, there is no known solution for solving these problems.
The ability of observers to view the source optics also adversely affects the performance and maintenance of the optics. For instance, some observers who see the source optics are prone to interfere with and vandalize them by throwing food, liquids or other objects at the source optics. Interference and vandalism of this nature can occlude the reflective surfaces of the source optics and thus severely inhibit generation of the real image. If the interference and vandalism are severe enough, the real image may be totally destroyed.
A further drawback associated with the visibility of the source optics is that it detracts from the observer's perception of depth and overlap of the real image, since the existing background behind the image invariably includes the source optics. This circumstance presents further significant limitations on the versatility and effective use of the real image.
At present, about the only practical solution to prevent interference by observers has been to place a glass shield between the source optics and the real image. These glass shields, which do not conceal the source optics, typically have an anti-reflective coating to help reduce the reflective properties of the glass. However, the anti-reflective coating undesirably decreases the transmissiveness of the glass shield such that the light level at the region of the real image is generally too low. As a result, the real image appears unrealistic and hard to see. Moreover, these glass shields, despite their anti-reflective coatings, still produce first-surface reflections and highlights which are distracting to the observers and which erode the intended effect of the real image.
The inability to conceal the source optics also places significant limitations on the visual effects that can be used in combination with the real image. If an anti-reflective glass shield is used, it still does not conceal the source optics, and the first-surface reflections and highlights certainly do not enhance the visual effects for the reasons discussed above. However, as also stated above, if the glass shield is not used, the source optics will be clearly unprotected. Hence, the quality and versatility of the present devices and methods for creating real image illusions is severely restricted.
Another drawback of current devices and methods for creating real image illusions resides in the limitations associated with the real object. The most common type of real object is a three-dimensional physical object. However, three-dimensional physical objects tend to be motionless and therefore produce very unimaginative real images. To the extent motion can be imparted to three-dimensional physical objects, it is very limited.
Accordingly, there has existed a definite need for an apparatus and method for creating a real image illusion in which the source optics are concealed from view by observers and which can be protected from damage or other observer-related interference. There further has existed a definite need for a real image illusion which enhances the observer's perception of depth and overlap of the real image with its background and which is free of restrictions when used in combination with other visual effects. The present invention satisfies these and other needs, and provides further related advantages.